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Note: For the 2016-17 season, CDC recommends use of the flu shot (inactivated influenza vaccine or IIV) and the recombinant influenza vaccine (RIV). The nasal spray flu vaccine (live attenuated influenza vaccine or LAIV) should not be used during 2016-17. The 2016-17 influenza vaccination recommendations are now available.

While current U.S. flu activity is low overall, localized influenza outbreaks have been reported and activity is expected to increase in the coming weeks.

CDC recommends a yearly flu vaccine for everyone 6 months and older. Now is a good time to get vaccinated. It takes about two weeks after vaccination for protection to set in.

Flu vaccination can reduce flu illnesses and prevent flu-related hospitalizations. Flu vaccines have been updated for the 2016-2017 season. More than 133 million doses of seasonal influenza vaccine have been distributed at this time.

CDC’s pandemic preparedness efforts include ongoing surveillance of human and animal influenza viruses, risk assessments of influenza viruses with pandemic potential, and the development and improvement of preparedness tools that can aid public health practitioners in the event of an influenza pandemic.

Bat influenza refers to influenza A viruses found in bats. Laboratory research at CDC suggests these viruses would need to undergo significant changes to become capable of infecting and spreading easily among humans. Little yellow shouldered bats are not native to the continental United States, but are common in Central and South America.

Influenza A viruses are found in humans and many different animals, including ducks, chickens, pigs, whales, horses and seals. Additional information on 2009 H1N1 influenza, Flu.gov, and Nonpharmaceutical Interventions (NPIs).

The latest report on CDC's international flu activities highlights the progress that has been made over the past two fiscal years in establishing, expanding and maintaining influenza surveillance and laboratory capacity in more than 50 countries around the world where CDC has provided support.